If \(K\sqrt{28}+\sqrt{63}-\sqrt{7}=0\), find K.
A
-2
B
-1
C
1
D
2
Verified Correct Answer: B.
Step-by-Step Mathematical Solution
\(K\sqrt{28}+\sqrt{63}-\sqrt{7}=0\\
2K\sqrt{7}+3\sqrt{7}-\sqrt{7}=0\\
2K\sqrt{7}=-2\sqrt{7}\\
K=\frac{-2\sqrt{7}}{2\sqrt{7}}\\
K=-1\)
Source: Myschool Past Questions Archive (Record #26382)